At present, portable computers, such as the type shown in FIG. 1, are widely used the world over. In the structure of this portable computer, the cathode-ray-tube (CRT) display A1 is pivotally connected to the host computer unit B1 by means of a pivot joint which is formed with a pair of lobes C1, C2 integrally provided at a back side of the CRT display A1 and a pair of pivot slots D1, D2 located in the host computer unit B1 for receiving a pair of pivot pins (not shown) separately connected to the lobes C1, C2 of the CRT display A1. With this manner of connection, the CRT display Al is placed on the host computer unit B1 as a covering member and can be operated to open and close along the pivot joint thereof when the associated portable computer is placed on a flat surface.
Although the conventional pivot joint as described above can function properly to perform the required opening and closing operations, an inconvenience may be encountered during the practical usage thereof. As shown in FIG. 2, the conventional pivot joint arranged in the portable computer can only enable the CRT display A1 to be lifted up at a fixed angle no matter where the host computer unit B1 is positioned. Since portable computers are designed not only to be placed on a desk but also to be placed wherever the user wishes according to his/her needs at the time, such as on his/her lap while sitting on an airplane, etc. Therefore, the fixed angle of elevation of the CRT display A1 cannot meet the requirements of the ordinary users who must carry their portable computers along with them when they need to work at a computer while away from the office.